In its tireless efforts to create smaller and more powerful structures for integrated circuits, Infineon Technologies AG (FSE/NYSE: IFX) has achieved a further breakthrough in its Munich laboratories: researchers here have constructed the world's smallest nanotube transistor, with a channel length of only 18 nm - the most advanced transistors currently in production are almost four times this size. To build their nanotransistor, the researchers grew carbon nanotubes, each one measuring only 0.7 to 1.1 nm in diameter, in a controlled process. A single human hair is around 100,000 times thicker by comparison.
The characteristic properties of carbon nanotubes make them the ideal candidate material for many applications in microelectronics: the tubes carry electrical current virtually without friction on their surface thanks to “ballistic” electron transport and can therefore handle 1000 times more than copper wire. What’s more, they can be both conducting and semiconducting. Infineon is one of the pioneers in developing carbon nanotubes and was the first semiconductor company to demonstrate how the tubes can be grown at precisely defined locations and how transistors for switching larger currents can be constructed.
The nanotube transistor just unveiled can deliver currents in excess of 15 µA at a supply voltage of only 0.4 V (0.7 V is currently the norm). A current density some 10 times above that of silicon, today's standard material, has been observed. On the basis of the test results, Infineon researchers are confident that they can go on miniaturizing transistors at the same rate as previously. Even supply voltages as low as 0.35 V, which are according to the ITRS currently not expected before the year 2018, could be realized if carbon nanotubes are used as the material.